Protective coating for footwear and other articles



Patented May 17, 1938 UNI-TE PROTE COATING FOR FOOEAR AND OTHER ARTICLES No Drawing.

Application June 29, 1935,

Serial No. 29,093 12 oi. (01. 12-142) This invention relates to the protection of articles during manufacture, shipping and storage and is especially useful in protecting articles of footwear or other articles which frequently in- 5 clude expensive and delicate fabrics or other materials which are easily damaged in the course of manufacture or while in transit or storage awaiting sale. The invention contemplates providing upon such articles adherent but readily l removable temporary protective coatings of rubher by a method which eliminates spotting, discoloration and other damage to the fabric by the coating material itself which has accompanied prior processes, and also aims to facilitate l subsequent removal of the rubber coatings by depositing upon the fabric, prior to the application of the rubber coating, a material which will prevent damage to the fabric by the vehicle in which the rubber is suspended for the purpose of application and which also will serve to. separate the rubber from the fabric to prevent undue adhesion with consequent difiiculty of subsequent removal.

In the manufacture of articles of footwear such as expensive shoes for women, highly finished fabricsand leathers which are quite sensi-l tive and easily damaged are utilized for various parts of the shoe, especially the uppers. In spite of the care exercised in handling such materials during manufacture of the shoe, they natural rubber latex and to dry the dispersion to provide upon the material an adherent but removable coating of rubber to serve as a protective means during manufacture and storage of the shoe part or the finished shoe. This proc- 5 ess has proved to be very satisfactory with some types of shoes and materials and has met with considerable favor in the shoe manufacturing industry, but it has not proved to be entirely satisfactory for use on shoes or shoe parts in- 50 eluding fabrics such as satins, moire, brocade, linen, and the like which have highly finished surfaces easily spotted, discolored or otherwise damaged by water, for the reason that the aqueous vehicle of the rubber latex or other aqueous dispersion itself spots or discolors the fabric and causes damage often equal to or more serious than that which would be caused by the grease and dirt, or by scufiing the finished surface. Additional damage to the finish is caused in many cases by mechanical disturbance of the relative arrangement of the surface fibers when the rubber coating is stripped from the fabric.

The present invention entirely overcomes these prior difficulties and makes possible the use of latex or other aqueous dispersions of rubber in coating the most sensitive and delicate fabrics, by coating the fabric, before application of the aqueous dispersion, with a water-repellent material designed to prevent direct contact of the aqueous vehicle with the' sensitive surface and also to facilitate subsequent stripping of the .drled rubber coating without damage to the finish. In a preferred form of the invention the water-repellent material comprises an oily liquid which is slowly volatile and which preferably contains a minor proportion of substantially nonvolatile material. rial is applied in any convenient manner to the fabric or shoe part to be protected and the aqueous dispersion of rubber then is superposed in any of the well known ways. The oily coating prevents direct contact between the fabric and the aqueous vehicle of the dispersion and thereby prevents spotting and discoloration of the fabric by the water until the dispersion is dried, but by virtue of its slow volatility the greater part of the oily coating evaporates after the dispersion has dried and disappears leaving the small proportion of less volatile material to serve as a separator between the rubber and the fabric and thereby to prevent undue adhesion and to facilitate subsequent stripping of the coating without damaging the fabric. In the preferred form of the invention, the less-volatile material serves also to enhance the sheen of the fabric and to aid in dyeing the fabric in those cases where it is dyed after its incorporation into the shoe. The oily liquid chosen may be and frequently will be at least slowly soluble in rubber in which case -itsremoval by volatilization will be supplemented by absorption of considerable quantities into the rubber. These and other features of the invention willbe more clearly understood from the following detailed description of some examples of the manner of utilizing the invention.

An upper for a woman's shoe is prepared in the usual manner from a satin fabric, but before its incorporation into the shoe it is sprayed, until a thin uniform coating has been applied, with a The water-repellent mateliquid composition consisting of 100 parts by weight of a safety solvent and 5 parts by weight of octyl alcohol. Then liquid rubber latex containing 50 to total solids is sprayed onto the coated fabric, preferably although not necessarily with simultaneous spraying of a coagulant for the latex as described in an application of Merrill E. Hansen, Serial No. 725,306 filed May 12, 1934. The coating of latex then is dried to provide upon the fabric a protective coating of rubber, and the coated fabric upper is lasted and built intoja shoe in the usual manner. At any time thereafter, the protective coating may be stripped off to expose the undamaged shoe. The octyl alcohol remaining on the surface of the fabric enhances its sheen and in some manner not fully understood at the present time also facilitates dyeingof the fabric.

The safety solvent" utilized in the foregoing example is one'of a number of commercial solvents now available which are understood to be petroleum products consisting of distillation cuts somewhat above the ordinary gasoline cuts and including large proportions of slowly volatile hydrocarbons principally of the paraffin series around and including octane. These particular cuts are especially useful in the present invention because they volatilize slowly enough to remain until the rubber is well dried and all danger of spotting of the fabric by water is past, but still are substantially completely volatilized in a reasonable time so that no oilymatter remains on the shoe when it is offered for sale. Also these cuts do not contain the more odoriferous higher members of the series which would be objectionable because of their odor. While it is understood that a number of safety solvents having varying distillation ranges are available, the solvents preferred for use in the presentv invention are those whose distillation ranges begin at a temperature not lower than 300 F. and endat a temperature not higher than 400 F.

In a second example, a shoe.upper made from a sensitive fabricv such as a moire,-or even a completed shoe including such material, is sprayed with a liquid composition consisting of 100 parts by weight of one of the.safety solvents containing 5 parts by weight 'of the commercial product prepared and sold by the E. I. du Pont de Nemours I & Company under the trade name Sperzo PAF and which is thought -t'o-b e a higher alcohol. Thereafter the fabric or shoe is coated with latex as hereinabove described to provide the desired adherent but readily removable protective coating.

In a third example the fabric or article of either of the foregoing examples is sprayed or otherwise coated with a liquid composition consisting of 100 parts by weight of an oily cyclic hydrocarbon such as xylene which may contain 5 parts by weight of a substantially non-volatile ester such as butyl stearate, after which a coating of an aqueous dispersion of rubber is superposed.

While the description thus far has related pri-- marily to the use of this invention in coating 'shoes and shoe fabrics, it is by no means limited to such use but may be utilized for protecting other articles having sensitive surfaces easily damaged by water. For example a highly finished article of furniture may be sprayed with.

ordinary gasoline or kerosene preferably although not necessarily containing 10 parts by weight of paraffin or a furniture wax, or the wax may be applied in the usual manner without the solvent, and thereafter an aqueous dispersion of rubber such as natural latex may be sprayed thereover to provide a protective coating of ru her. The gasoline or kerosene effectively prevents spotting of the furniture by the water vehicle of the latex but then evaporates, or is absorbed into the rubber, leaving a deposit of wax or paramn to separate the rubber from the furniture and to facilitate subsequent stripping. If a furniture wax is used either with or without .the solvent, a coatthe oily liquids hereinabove specifically mentioned others that have been found useful include coal tar high-flash naphthas, cymene, and like materials. Similarly, the less volatile constituent added to the solvent may be other higher alcohols, including the less-volatile liquid alcohols such as heptyl, octyl, nonyl alcohol and the like, as well as the still higher members of the series such as cetyl alcohol and others which are solids at ordinary room temperatures. As has been indicated, other substantially non-volatile or only slightly volatile esters such as butyl stearate, butyl oleate, butyl palmitate, and similar esters likewise may be used as the less-volatile member of the coating composition. Paramn, waxes, resins and the like which are soluble in the oily liquid also are useful in the coating composition, or such materials may in many cases be applied without a solvent vehicle as hereinabove described. It is to be understood that the "lessvolatile constituent of the water-repellent composition may be either a non-volatile material or a slowly volatile material which evaporates slowly enough to remain upon the coated material as long as required. If the superposed protective rubber coating is to remain upon, for example, a shoe part only during manufacture-of the shoe, as is frequently the case, a less volatile material which will volatilize in a few hours or even less may be used, but more frequently a substantially non-volatile material will be selected for this purpose so that .it will remain indefinitely upon the article.

Both the ,oily liquids and the aqueous dispersions of rubber utilized in this invention may be applied to the article to be protected in any convenient manner including spraying, brushing, dipping or the like, and other variations and whether natural or synthetic and whether in the a unvulcanized, vulcanized, or reclaimed condition.

The dispersions may be concentrated, diluted, thickened, thinned, compounded, pigmented, or otherwise preliminarily treated to condition them for the intended use.

We claim:

1. A method of manufacturing an article of I footwear including material likely to be damaged during manufacture of the article and which also is easily damaged by water, which comprises applying to said easily damaged material a waterrepellent coating comprising a volatile oily liquid containing dissolved therein a minor proportion of a separating material which is substantially less volatile than the oily liquid, superposing on the water-repellent coating, while it still con tains a substantial quantity of the volatile oily liquid, a coating of an aqueous dispersion of rubber, drying the aqueous dispersion to provide an adherent but readily removable protective coating of rubber upon said material, incorporating the coated material into an article of footwear, and thereafter stripping the protective rubber coating from the article.

2. A method as defined by claim 1 in which the volatile oily liquid has substantially the properties of a member of the group consisting of gasoline, kerosene, coal tar high flash naphtha, safety solvents and xylene.

3. A method as defined by claim 1 in which the volatile oily liquid is a petroleum product having a distillation range beginning not lower than 300 F. and ending not higher than 400 F.

4. A method as defined by claim 1 in which the volatile oily liquid is slowly soluble in rubber.

5. A method as defined by claim 1 in which the less volatile separating material dissolved in the volatile oily liquid is a material selected from the class consisting of higher alcohols and esters of fatty acids.

6. A method as defined by claim 1 in which the less volatile separating material dissolved in the volatile oily liquid is a higher alcohol.

'7. A method as defined by claim 1 in which the volatile oily liquid is a petroleum product having a distillation range beginning not lower than 300 F. and ending not higher than 400 F. and in which the less volatile separating material dissolved in the volatile oily liquid is a substantially non-volatile water-repellent organic material.

8. A method of providing fabric easily damaged by water with an adherent coating of rubber deposited in situ from an aqueous dispersion of rubber without damaging the fabric which comprises coating the fabric with a. film of a volatile oily liquid containing dissolved therein a minor proportion of a separating material which is substantially less volatile than the oily liquid, superposing on the said film, while it still contains a substantial quantity of the volatile oily liquid, a coating of an aqueous dispersion of rubber and drying the aqueous dispersion to provide an adherent coating of rubber.

9. A method of providing an article with an adherent but readily removable temporary protective coating of rubber which comprises applying to the surface of the article to be protected a thin coating of a water-repellent composition comprising a volatile oily liquid containing dissolved therein a minor proportion'of a separating material which is substantially less volatile than the oily liquid, superposing on the water-repellent coating, while it still contains a substantial quantity of the volatile oily liquid, a coating of an aqueous dispersion of rubber, and drying the aqueous dispersion to provide the desired protective coating of rubber.

10. An article of footwear including easily damaged material and comprising upon said material a thin water-repellent coating containing a slowly volatile oily liquid which is immiscible with water and a substantially less-volatile organic separating material, and superposed thereover an adherent but readily removable protective rubber coating.

11. An article of footwear including an easily damaged surface and comprising upon said surface a thin coating of water-repellent separating material comprising material selected from-the class consisting of higher alcohols and esters of fatty acids, and superposed thereover an adherent but readily removable protective rubber coating.

12. ,An article of manufacture including an easily damaged surface and comprising upon said surface a thin coating containing a slowly volatile, water-repellent oily liquid and a substantially less volatile organic separating material, and superposed thereover an adherent but readily removable protective rubber coating.

RAYMOND W. All-BRIGHT. ANDREW SZEGVARI. 

